Cardiovascular reactivity as a measure of irritability in a transdiagnostic sample of youth: Preliminary associations.

OBJECTIVES: Irritability is a transdiagnostic symptom in developmental psychopathology, conceptualized as a low threshold for frustration and increased proneness to anger. While central to emotion regulation, there is a vital need for empirical studies to explore the relationship between irritability and underlying physiological mechanisms of cardiovascular arousal. METHODS: We examined the relationship between irritability and cardiovascular arousal (i.e., heart rate [HR] and heart rate variability [HRV]) in a transdiagnostic sample of 51 youth (M = 12.63 years, SD = 2.25; 62.7% male). Data was collected using the Empatica E4 during a laboratory stop-signal task. In addition, the impact of motion activity, age, medication, and sleep on cardiovascular responses was explored. RESULTS: Main findings showed that irritability was associated with increased HR and decreased HRV during task performance. CONCLUSIONS: Findings support the role of peripheral physiological dysregulation in youth with emotion regulation problems and suggest the potential use of available wearable consumer electronics as an objective measure of irritability and physiological arousal in a transdiagnostic sample of youth.

The Clinician Affective Reactivity Index: Validity and Reliability of a Clinician-Rated Assessment of Irritability.

Irritability is impairing in youth and is the core feature of disruptive mood dysregulation disorder (DMDD). Currently, there are no established clinician-rated instruments to assess irritability in pediatric research and clinical settings. Clinician-rated measures ensure consistency of assessment across patients and are important specifically for treatment research. Here, we present data on the psychometric properties of the Clinician Affective Reactivity Index (CL-ARI), the first semistructured interview focused on pediatric irritability. The CL-ARI was administered to a transdiagnostic sample of 98 youth (M age = 12.66, SD = 2.47; 41% female). With respect to convergent validity, CL-ARI scores were (a) significantly higher for youth with DMDD than for any other diagnostic group, and (b) showed uniquely strong associations with other clinician-, parent-, and youth-report measures of irritability compared to measures of related constructs, such as anxiety. The three subscales of the CL-ARI (temper outbursts, irritable mood, impairment) showed excellent internal consistency. Test-retest reliability of the CL-ARI was adequate. These data support that irritability can be feasibly, validly, and reliably assessed by clinicians using the CL-ARI. A validated, gold-standard assessment of pediatric irritability is critical in advancing research and treatment efforts.